Oh yes, I agree with you on both counts:

deciding the relative value of things is deeply personal and very important if we care about individual people!

it’s not hierarchical to decide for yourself what you want and what you’re willing to give up in relation with other people, in fact i’d say understanding the necessity of that is a fundamental part of anarchism.

My point is that the more such decisions are quantitative in nature, the more like reciprocal relations are to turn into mercantile or even hierarchical ones.

There’s also the distinction between personal and public spheres. Value systems across either sphere can be radically different, but that’s a whole other can of beans (no pun intended).